MEASUREMENT OF ADHESIVE FORCE BETWEEN PARTICLES OF ORGANIC-SUBSTANCESAND POLYMER SUBSTRATES BY THE CENTRIFUGAL SEPARATION METHOD - EFFECT OF ELECTROSTATIC CHARGE

Effects of electrostatic force on adhesion between pharmaceutical powd er particles (phenacetin and sulfadimethoxine) and various polymer sub strates (polyethylene (PE), polyvinylchloride (PVC), Eudragit E100, po lyvinylacetal diethylamino acetate (AEA), Eudragit L30D-55) were inves tigated using the centrifugal separation technique, Two methods were u sed to attach powder particles to a substrate, the free falling method and the fluidization method, Average adhesive force, f(50), and elect ric potential, V, in the fluidized method were found to be greater tha n those in the free falling method for all the pharmaceutical powder/p olymer substrate systems examined, Average adhesive force, f(50), incr eased with a decrease in surface polarity, P-0, of polymer substrate f or each powder.